* Re: [PATCH 2/4] futex,plist: remove debug lock assignment for plist_node
2010-12-21 9:55 [PATCH 2/4] futex,plist: remove debug lock assignment for plist_node Lai Jiangshan
@ 2010-12-21 19:14 ` Darren Hart
2010-12-22 5:57 ` Lai Jiangshan
2010-12-22 16:24 ` Darren Hart
2011-03-12 10:58 ` [tip:core/futexes] futex,plist: Remove debug lock assignment from plist_node tip-bot for Lai Jiangshan
2 siblings, 1 reply; 6+ messages in thread
From: Darren Hart @ 2010-12-21 19:14 UTC (permalink / raw)
To: Lai Jiangshan
Cc: Peter Zijlstra, John Kacur, James Bottomley, Ingo Molnar,
Rafael J. Wysocki, Thomas Gleixner, Namhyung Kim, linux-kernel,
Steven Rostedt
On 12/21/2010 01:55 AM, Lai Jiangshan wrote:
> original code use&plist_node->plist as the faked head of
> the priority list for plist_del(), these debug locks in
> the faked head are needed for CONFIG_DEBUG_PI_LIST.
>
> But now we always pass the real head to plist_del(), the debug locks
> in plist_node will not be used, so we remove these assignments.
Any reason to keep this separate from patch 1/4 ?
--
Darren
>
> Signed-off-by: Lai Jiangshan<laijs@cn.fujitsu.com>
> ---
> diff --git a/kernel/futex.c b/kernel/futex.c
> index 6c4f67a..725834e 100644
> --- a/kernel/futex.c
> +++ b/kernel/futex.c
> @@ -1032,9 +1032,6 @@ void requeue_futex(struct futex_q *q, struct futex_hash_bucket *hb1,
> plist_del(&q->list,&hb1->chain);
> plist_add(&q->list,&hb2->chain);
> q->lock_ptr =&hb2->lock;
> -#ifdef CONFIG_DEBUG_PI_LIST
> - q->list.plist.spinlock =&hb2->lock;
> -#endif
> }
> get_futex_key_refs(key2);
> q->key = *key2;
> @@ -1068,9 +1065,6 @@ void requeue_pi_wake_futex(struct futex_q *q, union futex_key *key,
> q->rt_waiter = NULL;
>
> q->lock_ptr =&hb->lock;
> -#ifdef CONFIG_DEBUG_PI_LIST
> - q->list.plist.spinlock =&hb->lock;
> -#endif
>
> wake_up_state(q->task, TASK_NORMAL);
> }
> @@ -1418,9 +1412,6 @@ static inline void queue_me(struct futex_q *q, struct futex_hash_bucket *hb)
> prio = min(current->normal_prio, MAX_RT_PRIO);
>
> plist_node_init(&q->list, prio);
> -#ifdef CONFIG_DEBUG_PI_LIST
> - q->list.plist.spinlock =&hb->lock;
> -#endif
> plist_add(&q->list,&hb->chain);
> q->task = current;
> spin_unlock(&hb->lock);
--
Darren Hart
Yocto Linux Kernel
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH 2/4] futex,plist: remove debug lock assignment for plist_node
2010-12-21 19:14 ` Darren Hart
@ 2010-12-22 5:57 ` Lai Jiangshan
2010-12-22 6:47 ` Darren Hart
0 siblings, 1 reply; 6+ messages in thread
From: Lai Jiangshan @ 2010-12-22 5:57 UTC (permalink / raw)
To: Darren Hart
Cc: Peter Zijlstra, John Kacur, James Bottomley, Ingo Molnar,
Rafael J. Wysocki, Thomas Gleixner, Namhyung Kim, linux-kernel,
Steven Rostedt
On 12/22/2010 03:14 AM, Darren Hart wrote:
> On 12/21/2010 01:55 AM, Lai Jiangshan wrote:
>> original code use&plist_node->plist as the faked head of
>> the priority list for plist_del(), these debug locks in
>> the faked head are needed for CONFIG_DEBUG_PI_LIST.
>>
>> But now we always pass the real head to plist_del(), the debug locks
>> in plist_node will not be used, so we remove these assignments.
>
> Any reason to keep this separate from patch 1/4 ?
>
Make the changes clearer and the patches are easier to read.
For me the purposes of patch 1/4 and 2/4 are different,
1/4 makes the code sensible. 2/4 removes unused code.
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH 2/4] futex,plist: remove debug lock assignment for plist_node
2010-12-22 5:57 ` Lai Jiangshan
@ 2010-12-22 6:47 ` Darren Hart
0 siblings, 0 replies; 6+ messages in thread
From: Darren Hart @ 2010-12-22 6:47 UTC (permalink / raw)
To: Lai Jiangshan
Cc: Peter Zijlstra, John Kacur, James Bottomley, Ingo Molnar,
Rafael J. Wysocki, Thomas Gleixner, Namhyung Kim, linux-kernel,
Steven Rostedt
On 12/21/2010 09:57 PM, Lai Jiangshan wrote:
> On 12/22/2010 03:14 AM, Darren Hart wrote:
>> On 12/21/2010 01:55 AM, Lai Jiangshan wrote:
>>> original code use&plist_node->plist as the faked head of
>>> the priority list for plist_del(), these debug locks in
>>> the faked head are needed for CONFIG_DEBUG_PI_LIST.
>>>
>>> But now we always pass the real head to plist_del(), the debug locks
>>> in plist_node will not be used, so we remove these assignments.
>>
>> Any reason to keep this separate from patch 1/4 ?
>>
>
> Make the changes clearer and the patches are easier to read.
> For me the purposes of patch 1/4 and 2/4 are different,
> 1/4 makes the code sensible. 2/4 removes unused code.
Fair enough.
--
Darren Hart
Yocto Linux Kernel
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: [PATCH 2/4] futex,plist: remove debug lock assignment for plist_node
2010-12-21 9:55 [PATCH 2/4] futex,plist: remove debug lock assignment for plist_node Lai Jiangshan
2010-12-21 19:14 ` Darren Hart
@ 2010-12-22 16:24 ` Darren Hart
2011-03-12 10:58 ` [tip:core/futexes] futex,plist: Remove debug lock assignment from plist_node tip-bot for Lai Jiangshan
2 siblings, 0 replies; 6+ messages in thread
From: Darren Hart @ 2010-12-22 16:24 UTC (permalink / raw)
To: Lai Jiangshan
Cc: Peter Zijlstra, John Kacur, James Bottomley, Ingo Molnar,
Rafael J. Wysocki, Thomas Gleixner, Namhyung Kim, linux-kernel,
Steven Rostedt
On 12/21/2010 01:55 AM, Lai Jiangshan wrote:
> original code use&plist_node->plist as the faked head of
> the priority list for plist_del(), these debug locks in
> the faked head are needed for CONFIG_DEBUG_PI_LIST.
>
> But now we always pass the real head to plist_del(), the debug locks
> in plist_node will not be used, so we remove these assignments.
>
> Signed-off-by: Lai Jiangshan<laijs@cn.fujitsu.com>
Acked-by: Darren Hart <dvhart@linux.intel.com>
> ---
> diff --git a/kernel/futex.c b/kernel/futex.c
> index 6c4f67a..725834e 100644
> --- a/kernel/futex.c
> +++ b/kernel/futex.c
> @@ -1032,9 +1032,6 @@ void requeue_futex(struct futex_q *q, struct futex_hash_bucket *hb1,
> plist_del(&q->list,&hb1->chain);
> plist_add(&q->list,&hb2->chain);
> q->lock_ptr =&hb2->lock;
> -#ifdef CONFIG_DEBUG_PI_LIST
> - q->list.plist.spinlock =&hb2->lock;
> -#endif
> }
> get_futex_key_refs(key2);
> q->key = *key2;
> @@ -1068,9 +1065,6 @@ void requeue_pi_wake_futex(struct futex_q *q, union futex_key *key,
> q->rt_waiter = NULL;
>
> q->lock_ptr =&hb->lock;
> -#ifdef CONFIG_DEBUG_PI_LIST
> - q->list.plist.spinlock =&hb->lock;
> -#endif
>
> wake_up_state(q->task, TASK_NORMAL);
> }
> @@ -1418,9 +1412,6 @@ static inline void queue_me(struct futex_q *q, struct futex_hash_bucket *hb)
> prio = min(current->normal_prio, MAX_RT_PRIO);
>
> plist_node_init(&q->list, prio);
> -#ifdef CONFIG_DEBUG_PI_LIST
> - q->list.plist.spinlock =&hb->lock;
> -#endif
> plist_add(&q->list,&hb->chain);
> q->task = current;
> spin_unlock(&hb->lock);
--
Darren Hart
Yocto Linux Kernel
^ permalink raw reply [flat|nested] 6+ messages in thread
* [tip:core/futexes] futex,plist: Remove debug lock assignment from plist_node
2010-12-21 9:55 [PATCH 2/4] futex,plist: remove debug lock assignment for plist_node Lai Jiangshan
2010-12-21 19:14 ` Darren Hart
2010-12-22 16:24 ` Darren Hart
@ 2011-03-12 10:58 ` tip-bot for Lai Jiangshan
2 siblings, 0 replies; 6+ messages in thread
From: tip-bot for Lai Jiangshan @ 2011-03-12 10:58 UTC (permalink / raw)
To: linux-tip-commits; +Cc: linux-kernel, hpa, mingo, rostedt, dvhart, tglx, laijs
Commit-ID: 017f2b239dabb2740b91df162e004371b861f371
Gitweb: http://git.kernel.org/tip/017f2b239dabb2740b91df162e004371b861f371
Author: Lai Jiangshan <laijs@cn.fujitsu.com>
AuthorDate: Tue, 21 Dec 2010 17:55:10 +0800
Committer: Steven Rostedt <rostedt@goodmis.org>
CommitDate: Fri, 11 Mar 2011 15:09:53 -0500
futex,plist: Remove debug lock assignment from plist_node
The original code uses &plist_node->plist as the fake head of
the priority list for plist_del(), these debug locks in
the fake head are needed for CONFIG_DEBUG_PI_LIST.
But now we always pass the real head to plist_del(), the debug locks
in plist_node will not be used, so we remove these assignments.
Acked-by: Darren Hart <dvhart@linux.intel.com>
Signed-off-by: Lai Jiangshan <laijs@cn.fujitsu.com>
LKML-Reference: <4D10797E.7040803@cn.fujitsu.com>
Signed-off-by: Steven Rostedt <rostedt@goodmis.org>
---
kernel/futex.c | 9 ---------
1 files changed, 0 insertions(+), 9 deletions(-)
diff --git a/kernel/futex.c b/kernel/futex.c
index 6feeea4..9fe9131 100644
--- a/kernel/futex.c
+++ b/kernel/futex.c
@@ -1089,9 +1089,6 @@ void requeue_futex(struct futex_q *q, struct futex_hash_bucket *hb1,
plist_del(&q->list, &hb1->chain);
plist_add(&q->list, &hb2->chain);
q->lock_ptr = &hb2->lock;
-#ifdef CONFIG_DEBUG_PI_LIST
- q->list.plist.spinlock = &hb2->lock;
-#endif
}
get_futex_key_refs(key2);
q->key = *key2;
@@ -1124,9 +1121,6 @@ void requeue_pi_wake_futex(struct futex_q *q, union futex_key *key,
q->rt_waiter = NULL;
q->lock_ptr = &hb->lock;
-#ifdef CONFIG_DEBUG_PI_LIST
- q->list.plist.spinlock = &hb->lock;
-#endif
wake_up_state(q->task, TASK_NORMAL);
}
@@ -1474,9 +1468,6 @@ static inline void queue_me(struct futex_q *q, struct futex_hash_bucket *hb)
prio = min(current->normal_prio, MAX_RT_PRIO);
plist_node_init(&q->list, prio);
-#ifdef CONFIG_DEBUG_PI_LIST
- q->list.plist.spinlock = &hb->lock;
-#endif
plist_add(&q->list, &hb->chain);
q->task = current;
spin_unlock(&hb->lock);
^ permalink raw reply related [flat|nested] 6+ messages in thread